Anatomical basis for clamping of the right hepatic vein outside the liver during right hepatectomy.

The possibility and value of clamping the right hepatic vein (HV) outside the liver during right hepatectomy remain a matter of debate. We carried out an anatomical study on ten fresh cadaveric subjects with no abdominal scarring or hepatic lesions, to determine the biometry of the extraparenchymatous segment of the right HV. One or several accessory right HVs were found in 90% of cases on release of the right edge of the inferior vena cava (IVC). These accessory right HVs had a diameter greater than that of the superior right HV in 10% of cases. In 70% of cases, the extraparenchymatous segment of the vein was free of collateral branches, and in 30% of cases, it was joined by a branch close to its point of exit from the hepatic parenchyma. The length of the vein that can be clamped (length between the point of exit from the hepatic parenchyma and the point of entry of the right HV into the IVC) was 8.6 +/- 1.8 mm (6-12). The right HV entered the vena cava, at an acute angle, in 100% of cases. Clamping of the right HV was possible in all cases. Knowledge of these anatomical points makes it possible to isolate an extraparenchymatous segment of the right HV more safely. The right HV can be isolated and clamped outside the liver in more than 80% of cases, making it possible to carry out right hepatectomy on an exsanguinous liver.